Arduino Dot Matrix Game Console

#include "LedControl.h"
// connection to MAX7219 (data, clik, load, #of dispplay)
LedControl lc = LedControl(11,13,10,1);

// direction
const int TOP    = 0;
const int RIGHT  = 1;
const int BOTTOM = 2;
const int LEFT   = 3;
// Snake length
const int MAX_SNAKE_LENGTH = 16;

// Variables
//Adafruit_8x8matrix matrix = Adafruit_8x8matrix();  // Display
int direction = RIGHT;                               // direction of movement
int snakeX[MAX_SNAKE_LENGTH];                      // X-coordinates of snake
int snakeY[MAX_SNAKE_LENGTH];                      // Y-coordinates of snake
int snakeLength = 3;   
int score = 3;// 
unsigned long prevTime = 0;                        // for gamedelay (ms)
unsigned long delayTime = 500;                     // Game step in ms

int fruitX, fruitY;
unsigned long fruitPrevTime = 0;
unsigned long fruitBlinkTime = 100;
unsigned long bonusTime = 0;
unsigned long bonusPrevTime = 0;
int fruitLed = true;
int bonusLed = true;
int bonusX, bonusY;


void setup(){
  ////wake up the MAX72XX from power-saving mode
  lc.shutdown(0,false);
  //set a medium brightness for the Leds
  lc.setIntensity(0, 15);
  //Switch all Leds on the display off.
  lc.clearDisplay(0);
  Serial.begin(9600);
  
  randomSeed(analogRead(0));
  pinMode(0,INPUT);
  //pinMode(17,INPUT);
  pinMode(1,INPUT);
  pinMode(2,INPUT);
  pinMode(3,INPUT);
  pinMode(4,INPUT);
  pinMode(5,INPUT);
  //buzzer
  pinMode(12,OUTPUT);
  
  
  snakeX[0] = 0;
  snakeY[0] = 4;
  for(int i=1; i<MAX_SNAKE_LENGTH; i++){
    snakeX[i] = snakeY[i] = -1;
  }
  makeFruit();
  
}
  
void loop(){
    delay(10);
    checkButtons();  // if any button is pressed or not
   
    unsigned long currentTime = millis();
    if(currentTime - prevTime >= delayTime){
    nextstep(); 
    
    prevTime = currentTime;
  }
  draw(); // make snack & food
}

void checkButtons(){
  if(digitalRead(3)==0)
     direction = TOP;
  else if(digitalRead(4)==0)
     direction = RIGHT;
  else if(digitalRead(5)==0)
     direction = LEFT;
  else if(digitalRead(2)==0)
     direction = BOTTOM;
}

void draw(){
  lc.clearDisplay(0);
  drawSnake();
  drawFruit();

}
void drawSnake(){
  for(int i=0; i<snakeLength; i++){
    lc.setLed(0,snakeX[i], snakeY[i], true);
  }
}
void drawFruit(){
  if(inPlayField(fruitX, fruitY)){
    unsigned long currenttime = millis();
    if(currenttime - fruitPrevTime >= fruitBlinkTime){
      fruitLed = (fruitLed == true) ? false : true;
      fruitPrevTime = currenttime;
    }
    lc.setLed(0,fruitX, fruitY, fruitLed);
  }
}
boolean inPlayField(int x, int y){
  return (x>=0) && (x<8) && (y>=0) && (y<8);
}
void nextstep(){
    for(int i=snakeLength-1; i>0; i--){
    if((direction == RIGHT)&&(snakeX[0]-snakeLength == 7))
    snakeX[0] = -1;
    else if((direction == LEFT)&&(snakeX[0]+ snakeLength == 0))
    snakeX[0] = 8;
    else snakeX[i] = snakeX[i-1];
    if((direction == TOP) && (snakeY[0]+snakeLength == 0))
    snakeY[0]=8;
    else if((direction == BOTTOM) && (snakeY[0]-snakeLength == 7))
    snakeY[0]=-1;
    else snakeY[i] = snakeY[i-1];      
  }
  switch(direction){
    case TOP:
      snakeY[0] = snakeY[0]-1; 
      break;
    case RIGHT:
      snakeX[0] = snakeX[0]+1;
      break;
    case BOTTOM:
      snakeY[0] = snakeY[0]+1;
      break;
    case LEFT:
      snakeX[0]=snakeX[0]-1;
      break;
   }
  if((snakeX[0] == fruitX) && (snakeY[0] == fruitY)){
    snakeLength++;
    score++;
    tone(12,4500,50);
    if(snakeLength < MAX_SNAKE_LENGTH){      
      makeFruit();
    } 
    else {
      fruitX = fruitY = -1;
    }
    if(score%8==0)
      {
        snakeLength = 3;
        delayTime = delayTime - 100;
     }
  }
  snakeItSelf();  
}
void makeFruit(){
  int x, y;
  x = random(0, 8);
  y = random(0, 8);
  while(isPartOfSnake(x, y)){
    x = random(0, 8);
    y = random(0, 8);
  }
  fruitX = x;
  fruitY = y;
}

boolean isPartOfSnake(int x, int y){
  for(int i=0; i<snakeLength-1; i++){
    if((x == snakeX[i]) && (y == snakeY[i])){
      return true;
    }
  }
  return false;
}
void snakeItSelf(){  // check if snack touch itself
    for(int i=1;i<snakeLength;i++){
      if((snakeX[0] == snakeX[i]) && (snakeY[0] == snakeY[i]))
       gameOver();
     }
}
void gameOver(){
  // game over sound
  tone(12,1000,100);
  delay(100);
  tone(12,1500,200);
  delay(200);
  tone(12,2000,300);
  delay(300);
  tone(12, 494,500);
  delay(500);
  lc.clearDisplay(0);
  for(int r = 0; r < 8; r++){
        for(int c = 0; c < 8; c++){
            lc.setLed(0, r, c, HIGH);
            delay(50);
        }delay(50);
    }
  delay(300);
  score = 3;  
  snakeLength = 3;
  direction = RIGHT;
  snakeX[0]=3;
  snakeY[0]=4;
  delayTime = 500;
  loop();
}

void drawBonus(){
  if(inPlayField(fruitX, fruitY)){
    unsigned long bonusTime = millis();
    if(bonusTime - bonusPrevTime >= 300){
      bonusLed = (bonusLed == true) ? false : true;
      bonusPrevTime = bonusTime;
    }
    lc.setLed(0,bonusX, bonusY, bonusLed);
  }
}
void makeBonus(){
  int x, y;
  x = random(0, 8);
  y = random(0, 8);
  while(isPartOfSnake(x, y)){
    x = random(0, 8);
    y = random(0, 8);
  }
  bonusX = x;
  bonusY = y;
}